Both incense burners give the same prayer bonus. The player must have a clean marrentill. For maximum prayer bonus, both burners have to be lit.

The burners burn 2 minutes and 10 seconds before they burn out. They will not stay lit when all players have left the house. However, if there are other players in the house when the owner leaves through the entrance portal; they will stay lit as long as the owner returns to the house within 5 seconds, effectively making it possible for hosts to advertise for themselves or check to make sure their advertiser is doing their job.